From: Ryan Bradetich <rbradetich@uswest.net>
To: Randolph Chung <randolph@tausq.org>
Cc: parisc-linux@lists.parisc-linux.org
Subject: Re: [parisc-linux] DIFF use 6-regs in copy_user_page_asm
Date: Tue, 04 Jan 2005 01:23:06 -0700 [thread overview]
Message-ID: <1104826986.8221.8.camel@beavis> (raw)
In-Reply-To: <20050104061342.GE18497@tausq.org>
Randolph,
Is this something that would benefit older processors? Say a PCX-T
processor? Is this something worth testing? I'm pretty sure I
have a PCX-T processor around I could boot up and test.
- Ryan
On Mon, 2005-01-03 at 22:13 -0800, Randolph Chung wrote:
> > This patch adds one more cycle between the load and store of a
> > given register by using three pairs of registers instead of two.
> > I had previously quoted one of the PA-8xxx papers that indicated
> > L1 cache was 2 cycles latency.
> > With this diff, the unrolled part of the loop now meets that.
> > The prolog and epilogue obviously cannot.
> >
> > If anyone can show me a workload that improves with this diff,
> > I'll apply it. Otherwise it's just an academic excercise.
>
> i'd like to see numbers too, but i doubt you will see any. it appears
> that at least newer PA cpus do a sufficient amount of internal
> instruction reordering that you don't see a difference as long as there
> are enough pending instructions to keep the pipeline busy.
>
> randolph
--
Ryan Bradetich <rbradetich@uswest.net>
_______________________________________________
parisc-linux mailing list
parisc-linux@lists.parisc-linux.org
http://lists.parisc-linux.org/mailman/listinfo/parisc-linux
next prev parent reply other threads:[~2005-01-04 8:23 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2005-01-03 6:19 [parisc-linux] DIFF use 6-regs in copy_user_page_asm Grant Grundler
2005-01-04 6:13 ` Randolph Chung
2005-01-04 8:23 ` Ryan Bradetich [this message]
2005-01-04 8:29 ` Randolph Chung
2005-01-04 13:12 ` Joel Soete
2005-01-04 14:51 ` Michael S. Zick
2005-01-04 16:02 ` Grant Grundler
[not found] ` <200501041142.44400.mszick@wolfbutter.com>
2005-01-04 20:09 ` Grant Grundler
2005-01-04 23:39 ` Grant Grundler
2005-01-05 0:00 ` John David Anglin
2005-01-05 22:01 ` Michael S. Zick
2005-01-06 22:55 ` Grant Grundler
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1104826986.8221.8.camel@beavis \
--to=rbradetich@uswest.net \
--cc=parisc-linux@lists.parisc-linux.org \
--cc=randolph@tausq.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox